Optimism, But No Breakthrough In Search For Malaysian Jet

Sgt. Trent Wyatt looks out an observation window on Friday from aboard a Royal New Zealand air force P-3 Orion maritime search aircraft as it flies over the southern Indian Ocean. So far there's been no sign of Malaysian Airlines Flight 370. But officials are hoping that sounds detected below the surface are coming from one or both of the plane's black boxes.

Australian Prime Minister Tony Abbott said he is "very confident" that pings detected by searchers this week in the south Indian Ocean are coming from one or both of the plane's two black boxes that record flight data and cockpit conversations. NPR's Anthony Kuhn reports that Abbott said it's his understanding the signals have significantly narrowed the focus of the search.

But Angus Houston, the retired Australian air defense chief who is leading the search effort, said Friday that "[based] on the information I have available to me, there has been no major breakthrough."

Houston also said it has been determined that the latest sound picked up by searchers, which was detected Thursday, "is unlikely to be related to the aircraft black boxes."

What's more, Houston said, it "could be some days" before it's decided whether the other sounds detected so far warrant sending an unmanned vehicle down to the seafloor. On Friday, the focus of the multinational searchers' operations was on three zones from 1,000 miles to about 1,500 miles northwest of Perth, Australia. The waters are about 3 miles deep.

"It is vital to glean as much information as possible" about the black boxes' possible locations "while the batteries on the underwater locator beacons may still be active," he said. Experts say those batteries likely began to fade after about 30 days in water. This is Day 35.

The jet was about one hour into a flight from Kuala Lumpur to Beijing in the early morning hours of March 8 (local time) when it was last heard from. Flight 370 was headed north over the Gulf of Thailand as it approached Vietnamese airspace.

Investigators believe the plane turned west, flew back over the Malay Peninsula, then out over the Indian Ocean before turning south toward Australia. They're basing those conclusions largely on data collected by a satellite system that received some information from the aircraft. The critical question — why did it turn? — remains unanswered.